Hooghiemstra, H; Cleef, AM; van Geel, B; Almeida-Leñero, Lucia
(2005)
Pollen records of a 520-cm long core from Lake Zempoala (2800 m altitude) and a 884-cm long composite core from Lake Quila (3010 m altitude), both located 65 km SW of Mexico City, show changes in vegetation and climate. ...